Lock-in insulator



April 1958 F. E. PRow'AN-r 2,831,915

LOCK-IN INSULATOR Filed Nov. 28, 1955 Fig./

Fred 5. Prowan/ INVENTOR.

Amme]:

LOCK-IN INSULATOR Fred E. Prowant, Chadwick, Ill.

Application November 28, 1955, Serial N 0. 549,306

2 Claims. (Cl. 174-158) 7 This invention relates to insulators adapted to support I live wires or other elongated objects.

An object of the present invention is to provide an insulator which may be connected to any suitable support, as a fence post, the insulator having a locking feature which retains a live wire therein preventing the wire from grounding, becoming loose and holding the wire safely and securely.

A further object of the invention is'to provide an inexpensive insulator of the type usable to support high or low tension wires, the insulator including a cradle in which to mount the wire together with a locking device operatively connected with the cradle and means extending from the wire cradle for mounting the insulator on a support.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a perspective view of the insulator showing the same used in connection with a post and supporting an electrical conductor;

Figure 2 is an elevational view of the insulator of Figure 1 with parts being shown in section to illustrate internal detail;

Figure 3 is a side view of the insulator of Figure 2 showing the locking means in the opened position to accept an electric wire; and

Figure 4 is a top view of the structure in Figure 1, the locking device being shown in section.

In the accompanying drawing I have shown a vertical support that has a laterally extending threaded lug 12 projecting therefrom. It is assumed that the support 10 is a part of a fence, although the improved insulator need not be used exclusively in the connection with fencmg.

The insulator 14 consists of a shank 16 having an internally threaded bore 18 at one end in which the threaded stud is adapted to be disposed. Having the connection between the threaded bore 18 and the stud 12 mounts the insulator 14 in the operative position. i

. UnitedStates Patent 0 The outer end of the shank 16 has an eye 20, the eye adapted to have a conductor, for example wire 21 passed therethrough. The eye is made of two pieces, that is the cradle 22 and locking device 24 operatively associated with it. The cradle is made circular with an entrance notch 26 in it. Locking device 24 comprises a keeper 28 having a tongue 30 protruding from one end thereof and fitted between the pair of ears 31 and 32 formed as a portion of the cradle. Keeper 28 has a pivot pin 34 passed through the tongue 30, this pin passing also Patented Apr. 22, 1958 through ears 31 and 32. A resilient wire bale 35 is pivoted to the keeper 28 and includes two side members 36 and 37 which converge to a junction 40 and which are bent near their junction. The bent portions of the sides 36 and 37 fit flush against the outer surface of the cradle 22 near the protuberance 42 which rises from that surface. Sides 36 and 37 at junction 40 frictionally engage the protuberance 42 in order to hold the bale 35 frictionally clamped with the cradle 22.

It is intended that the entire insulator be made of electrically insulating material with the exception of those parts which must withstand mechanical stresses in their use so as to make insulating material impractical. For example, the wire bale 35 must be resilient and therefore metal is suggested. The pivot pin 34 must be strong and capable of withstanding repeated movements thereon. Therefore metal is suggested for this part.

In use the shank 16 is threaded on a stud 12 or is otherwise rigidly fixed. The conductor 20 is rested in the generally circular aperture 50 formed in the eye of the insulator. Then the keeper 28 is swung pivotally until the surface 51 thereof comes to rest against the surface 52 of the cradle 22. Then the wire bale 35 is plvotally swung so that the junction 40 of the two sides of the wire bale snaps over the protuberance 42 holding the keeper 28 locked in place. By use of the insulator described the conductor 20 may be easily inserted and removed from the insulator and yet, it is held very fast and firm.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable moifications and equivalents may be resorted to, falling within the scope ofthe invention as claimed.

What is claimed as new is as'follows:

1. An insulator for an electrical conductor, said insulator comprising an insulating shank having a support receiving opening at one end and a cradle at the other end of said shank said cradle having a wirereceiving cradle surface with an entrance for access to said surface, said cradle being of electrically insulating material, a keeper having a tongue protruding from one end thereof, said cradle having a pair of spaced ears between which said tongue is disposed, said tongue and ears having aligned apertures, a pivot pin passed through said aligned apertures thereby mounting said keeper for pivotal movement on said cradle, said keeper and said cradle having stop surfaces which are adapted to be in contact with each other when said keeper isin the entrance closing position, and means operatively connected with said keeper and said cradle for releasably holding said keeper in the entrance closing position.

2. The insulator of claim 1 wherein said means operatively connected with said keeper and said cradle for releasably holding said keeper in the entrance closing position comprise a bail which is pivoted to said keeper, a protuberance on said cradle over which said bail'is movable to a frictional engagement position for holding said keeper in said entrance closing position.

References Cited in the file of this patent V UNITED STATES PATENTS Marth Feb. 8, 1955 

